scholarly journals The evolutionary history of haptophytes and cryptophytes: phylogenomic evidence for separate origins

2012 ◽  
Vol 279 (1736) ◽  
pp. 2246-2254 ◽  
Author(s):  
Fabien Burki ◽  
Noriko Okamoto ◽  
Jean-François Pombert ◽  
Patrick J. Keeling
Keyword(s):  
Evolutionary History ◽  
Expressed Sequence Tag ◽  
Level Data ◽  
Guillardia Theta ◽  
History Of ◽  
The Common ◽  
Genome Level ◽  
Phylogenomic Analyses ◽  
New Hypothesis ◽  
Expressed Sequence

An important missing piece in the puzzle of how plastids spread across the eukaryotic tree of life is a robust evolutionary framework for the host lineages. Four assemblages are known to harbour plastids derived from red algae and, according to the controversial chromalveolate hypothesis, these all share a common ancestry. Phylogenomic analyses have consistently shown that stramenopiles and alveolates are closely related, but haptophytes and cryptophytes remain contentious; they have been proposed to branch together with several heterotrophic groups in the newly erected Hacrobia. Here, we tested this question by producing a large expressed sequence tag dataset for the katablepharid Roombia truncata , one of the last hacrobian lineages for which genome-level data are unavailable, and combined this dataset with the recently completed genome of the cryptophyte Guillardia theta to build an alignment composed of 258 genes. Our analyses strongly support haptophytes as sister to the SAR group, possibly together with telonemids and centrohelids. We also confirmed the common origin of katablepharids and cryptophytes, but these lineages were not related to other hacrobians; instead, they branch with plants. Our study resolves the evolutionary position of haptophytes, an ecologically critical component of the oceans, and proposes a new hypothesis for the origin of cryptophytes.

First North African record of a melanistic common genet (Genetta genetta Linnaeus, 1758)

Mammalia ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mourad Ahmim ◽  
Hafid Aroudj ◽  
Farouk Aroudj ◽  
Saaid Saidi ◽  
Samir Aroudj
Keyword(s):  
North Africa ◽  
Evolutionary History ◽  
North African ◽  
Mammal Species ◽  
Genetta Genetta ◽  
History Of ◽  
The Common ◽  
True Occurrence

Abstract The common genet (Genetta genetta Linnaeus, 1758) is a rare and protected mammal species in Algeria. We report the first melanistic individual of this species ever recorded in North Africa. Such animals have only been recorded in Spain and Portugal so far. It is unclear why melanistic common genets seem to be so rare in its African range. More research is needed to determine the true occurrence of melanistic individuals, and what the evolutionary history of melanism is in common genets.

scholarly journals The evolutionary history of the two karyotypic groups of the common shrew, Sorex araneus, in Poland

Heredity ◽  
2002 ◽  
Vol 88 (4) ◽  
pp. 235-242 ◽  
Author(s):  
M Ratkiewicz ◽  
S Fedyk ◽  
A Banaszek ◽  
L Gielly ◽  
W Chȩtnicki ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Common Shrew ◽  
Sorex Araneus ◽  
History Of ◽  
The Common ◽  
Common Shrew Sorex Araneus

scholarly journals Tribalism Is Human Nature

2019 ◽  
Vol 28 (6) ◽  
pp. 587-592 ◽  
Author(s):  
Cory J. Clark ◽  
Brittany S. Liu ◽  
Bo M. Winegard ◽  
Peter H. Ditto
Keyword(s):  
Evolutionary History ◽  
Cognitive Biases ◽  
Meta Analysis ◽  
Human Cognition ◽  
Partisan Bias ◽  
Selective Pressures ◽  
Group Loyalty ◽  
History Of ◽  
The Common ◽  
Political Spectrum

Humans evolved in the context of intense intergroup competition, and groups comprised of loyal members more often succeeded than groups comprised of nonloyal members. Therefore, selective pressures have sculpted human minds to be tribal, and group loyalty and concomitant cognitive biases likely exist in all groups. Modern politics is one of the most salient forms of modern coalitional conflict and elicits substantial cognitive biases. The common evolutionary history of liberals and conservatives gives little reason to expect protribe biases to be higher on one side of the political spectrum than the other. This evolutionarily plausible null hypothesis has been supported by recent research. In a recent meta-analysis, liberals and conservatives showed similar levels of partisan bias, and several protribe cognitive tendencies often ascribed to conservatives (e.g., intolerance toward dissimilar other people) were found in similar degrees in liberals. We conclude that tribal bias is a natural and nearly ineradicable feature of human cognition and that no group—not even one’s own—is immune.

scholarly journals Phylogenomic Reconstruction Sheds Light on New Relationships and Timescale of Rails (Aves: Rallidae) Evolution

Diversity ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 70 ◽  
Author(s):  
Juan C. Garcia-R ◽  
Emily Moriarty Lemmon ◽  
Alan R. Lemmon ◽  
Nigel French
Keyword(s):  
Evolutionary History ◽  
State Of The Art ◽  
Molecular Techniques ◽  
Evolutionary Significance ◽  
Phylogenetic Structure ◽  
Bayesian Approaches ◽  
Phylogenetic Studies ◽  
Anchored Phylogenomics ◽  
History Of ◽  
Phylogenomic Analyses

The integration of state-of-the-art molecular techniques and analyses, together with a broad taxonomic sampling, can provide new insights into bird interrelationships and divergence. Despite their evolutionary significance, the relationships among several rail lineages remain unresolved as does the general timescale of rail evolution. Here, we disentangle the deep phylogenetic structure of rails using anchored phylogenomics. We analysed a set of 393 loci from 63 species, representing approximately 40% of the extant familial diversity. Our phylogenomic analyses reconstruct the phylogeny of rails and robustly infer several previously contentious relationships. Concatenated maximum likelihood and coalescent species-tree approaches recover identical topologies with strong node support. The results are concordant with previous phylogenetic studies using small DNA datasets, but they also supply an additional resolution. Our dating analysis provides contrasting divergence times using fossils and Bayesian and non-Bayesian approaches. Our study refines the evolutionary history of rails, offering a foundation for future evolutionary studies of birds.

scholarly journals Most Compositae (Asteraceae) are descendants of a paleohexaploid and all share a paleotetraploid ancestor with the Calyceraceae

2016 ◽  
Author(s):  
Michael S. Barker ◽  
Zheng Li ◽  
Thomas I. Kidder ◽  
Chris R. Reardon ◽  
Zhao Lai ◽  
...  
Keyword(s):  
Gene Family ◽  
Linkage Map ◽  
Evolutionary History ◽  
Genome Duplication ◽  
Nuclear Gene ◽  
Flowering Plants ◽  
The Family ◽  
History Of ◽  
Phylogenomic Analyses

AbstractPremise of the studyLike many other flowering plants, members of the Compositae (Asteraceae) have a polyploid ancestry. Previous analyses found evidence for an ancient duplication or possibly triplication in the early evolutionary history of the family. We sought to better place this paleopolyploidy in the phylogeny and assess its nature.MethodsWe sequenced new transcriptomes for Barnadesia, the lineage sister to all other Compositae, and four representatives of closely related families. Using a recently developed algorithm, MAPS, we analyzed nuclear gene family phylogenies for evidence of paleopolyploidy.Key resultsWe found that the previously recognized Compositae paleopolyploidy is also in the ancestry of the Calyceraceae. Our phylogenomic analyses uncovered evidence for a successive second round of genome duplication among all sampled Compositae except Barnadesia.ConclusionsOur analyses of new samples with new tools provide a revised view of paleopolyploidy in the Compositae. Together with results from a high density Lactuca linkage map, our results suggest that the Compositae and Calyceraceae have a common paleotetraploid ancestor and most Compositae are descendants of a paleohexaploid. Although paleohexaploids have been previously identified, this is the first example where the paleotetraploid and paleohexaploid lineages have survived over tens of millions of years. The complex polyploidy in the ancestry of the Compositae and Calyceraceae represents a unique opportunity to study the long-term evolutionary fates and consequences of different ploidal levels.

scholarly journals Biomineral ultrastructure, elemental constitution and genomic analysis of biomineralization-related proteins in hemichordates

2012 ◽  
Vol 279 (1740) ◽  
pp. 3041-3048 ◽  
Author(s):  
C. B. Cameron ◽  
C. D. Bishop
Keyword(s):  
Expressed Sequence Tag ◽  
Genomic Analysis ◽  
Mineralized Tissue ◽  
Saccoglossus Kowalevskii ◽  
Ptychodera Flava ◽  
The Common ◽  
Gene Regulatory ◽  
Related Proteins ◽  
Expressed Sequence

Here, we report the discovery and characterization of biominerals in the acorn worms Saccoglossus bromophenolosus and Ptychodera flava galapagos (Phylum: Hemichordata). Using electron microscopy, X-ray microprobe analyses and confocal Raman spectroscopy, we show that hemichordate biominerals are small CaCO 3 aragonitic elements restricted to specialized epidermal structures, and in S. bromophenolosus, are apparently secreted by sclerocytes. Investigation of urchin biomineralizing proteins in the translated genome and expressed sequence tag (EST) libraries of Saccoglossus kowalevskii indicates that three members of the urchin MSP-130 family, a carbonic anhydrase and a matrix metaloprotease are present and transcribed during the development of S. kowalevskii . The SM family of proteins is absent from the hemichordate genome. These results increase the number of phyla known to biomineralize and suggest that some of the gene-regulatory ‘toolkit’, if not mineralized tissue themselves, may have been present in the common ancestor to hemichordates and echinoderms.

Bridging Darwin's Origin of Species & Wegener's Origin of Continents and Oceans:

2016 ◽  
Vol 78 (1) ◽  
pp. 24-33 ◽  
Author(s):  
Cristina Sousa
Keyword(s):  
Evolutionary History ◽  
Charles Darwin ◽  
Common Ancestor ◽  
Teaching Strategy ◽  
Origin Of Species ◽  
History Of ◽  
The Common ◽  
Research And Education ◽  
Evolution By Natural Selection ◽  
Biology Research

The common ancestor and evolution by natural selection, concepts introduced by Charles Darwin, constitute the central core of biology research and education. However, students generally struggle to understand these concepts and commonly form misconceptions about them. To help teachers select the most revelant portions of Darwin's work, I suggest some sentences from On the Origin of Species and briefly discuss their implications. I also suggest a teaching strategy that uses history of science and curriculum crosscutting concepts (cause and effect) that constitute the framework to explain the evolutionary history of ratites (flightless birds) as described by Darwin, starting in the Jurassic, with the breakup of Gondwanaland, as first described by Alfred Wegener in The Origin of Continents and Oceans.

Phlogopitization of pyroxenite; its bearing on the composition of carbonatite magmas

1975 ◽  
Vol 112 (5) ◽  
pp. 503-507 ◽  
Author(s):  
J. Gittins ◽  
C. R. Allen ◽  
A. F. Cooper
Keyword(s):  
Evolutionary History ◽  
Ultramafic Rock ◽  
Aqueous Fluid ◽  
Typical Development ◽  
Experimental Phase ◽  
Carbonatite Complex ◽  
History Of ◽  
The Common ◽  
Alumina Activity ◽  
Carbonatite Magma

SummaryPhlogopitization of pyroxenite is common in contact zones between clinopyroxenites and carbonatite dikes of the Cargill ultramafic rock—carbonatite complex near Kapuskasing, Ontario. The most typical development is a mica zone 1–10 cm wide but phlogopite is also developed in a more pervasive manner throughout the groundmass of several types of ultramafic rock. Fenitization is most commonly thought of as a process whereby aegirine and riebeckitic amphiboles are formed in the host rock while feldspar is recrystallized and silica progressively removed. Phlogopitization of pyroxenite can properly be referred to, however, as a type of fenitization. It is clearly related to the intrusion of carbonatite into pyroxenite and is further testimony to the fact that many carbonatite magmas are initially alkalic but lose alkalies to the surrounding rocks and crystallize as calcitic and dolomitic carbonatite with alkali contents restricted to the amounts that could be fixed as micas, pyroxenes or amphiboles. This in turn is controlled by the silica and alumina activity of the carbonatite magma. Abundant evidence for considerable amounts of fluorine in carbonatite magmas suggests that alkalies may be transported into the country rocks as fluorides. It is further suggested that late-stage feldspathization in carbonatite complexes is explained by the abstraction of potassic halide solutions from the crystallizing carbonatite magma. The conclusion seems inescapable that alkali carbonatite magmas, far from being the curiosity thought by many petrologists, are in fact very common during the evolutionary history of carbonatites. The common calcitic and dolomitic carbonatites have not generally crystallized from a magma of the same composition but are the residue remaining after the abstraction of an alkali-rich aqueous fluid. Consequently, there is a need to redesign the experimental phase equilibrium approach to problems of carbonatite genesis in order to take account of the presence of alkalies in most carbonatite magmas.

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